A turn-down collar is preferred for black tie as a wing collar would reveal the band of the bow tie. A proper wing collar should be detachable and laundered by a specialist, a hassle which few are willing to tolerate today.
A proper tuxedo shirt should only have three stud holes. While a stud set will have four studs, the fourth stud is a spare. Shirts with four stud holes perhaps were made without awareness of this convention.
As with all shirts, machine wash cold on the gentle cycle and hang dry only. Heated drying will shorten the life of your shirt, as will the chemicals used in dry cleaning. A few minutes in the dryer on the no heat, air puff cycle before hang drying will reduce wrinkling. Also avoid bleach, fabric softener, and starch as much as possible. It's best to wash your shirts yourself, but any good cleaner, given these instructions, will suffice.
Over a few washes, if hang dried, shrinkage will be almost imperceptible. The neck will shrink about 0.25" and the shirt length and sleeve length about 0.5". If machine dried, shrinkage may be around 1". We cannot accept returns on washed or worn garments.
Additional spare buttons are available at no charge.